django-celery-transactions holds on to Celery tasks until the current database transaction is committed, avoiding potential race conditions as described in Celery's user guide. Send tasks from signal handlers without fear!
commit_manually
, commit_on_success
, etc.Install django-celery-transactions from PyPI:
$ pip install django-celery-transactions
Use the patched decorator to create your tasks:
from djcelery_transactions import task
from models import Model
@task
def print_model(model_pk):
print Model.objects.get(pk=model_pk)
Then use them as normal:
from django.db import transaction
from models import Model
from tasks import print_model
# This task will be sent after the transaction is committed. This works
# from anywhere in the managed transaction block (e.g. signal handlers).
def view(request):
model = Model.objects.create(...)
print_model.delay(model.pk)
# This task will not be sent (it is discarded) as the transaction
# middleware rolls the transaction back when it catches the exception.
def failing_view(request, model_pk):
print_model.delay(model_pk)
raise Exception()
# This task will be sent immediately as transactions aren't being
# managed and it is assumed that the author knows what they're doing.
@transaction.commit_manually
def manual_view(request, model_pk):
print_model.delay(model_pk)
transaction.commit()
$ python setup.py test